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  <div class="SECT1">
    <h1 class="SECT1"><a name="TROUBLE" id="TROUBLE">5.
    Troubleshooting</a></h1>

    <div class="SECT2">
      <h3 class="SECT2"><a name="AEN1100" id="AEN1100">5.1. I cannot connect
      to any websites. Or, I am getting <span class="QUOTE">"connection
      refused"</span> message with every web page. Why?</a></h3>

      <p>There are several possibilities:</p>

      <ul>
        <li>
          <p><span class="APPLICATION">Privoxy</span> is not running.
          Solution: verify that <span class="APPLICATION">Privoxy</span> is
          installed correctly, has not crashed, and is indeed running. Turn
          on <span class="APPLICATION">Privoxy's</span> logging, and look at
          the logs to see what they say.</p>
        </li>

        <li>
          <p>Or your browser is configured for a different port than what
          <span class="APPLICATION">Privoxy</span> is using. Solution: verify
          that <span class="APPLICATION">Privoxy</span> and your browser are
          set to the same port (<tt class="LITERAL">listen-address</tt>).</p>
        </li>

        <li>
          <p>Or if using a forwarding rule, you have a configuration problem
          or a problem with a host in the forwarding chain. Solution:
          temporarily alter your configuration and take the forwarders out of
          the equation.</p>
        </li>

        <li>
          <p>Or you have a firewall that is interfering and blocking you.
          Solution: try disabling or removing the firewall as a simple
          test.</p>
        </li>
      </ul>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="ERROR503" id="ERROR503">5.2. Why am I
      getting a 503 Error (WSAECONNREFUSED) on every page?</a></h3>

      <p>More than likely this is a problem with your TCP/IP networking.
      ZoneAlarm has been reported to cause this symptom -- even if not
      running! The solution is to either fight the ZA configuration, or
      uninstall ZoneAlarm, and then find something better behaved in its
      place. Other personal firewall type products may cause similar type
      problems if not configured correctly.</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="AEN1123" id="AEN1123">5.3. I just added a
      new rule, but the steenkin ad is still getting through. How?</a></h3>

      <p>If the ad had been displayed before you added its URL, it will
      probably be held in the browser's cache for some time, so it will be
      displayed without the need for any request to the server, and
      <span class="APPLICATION">Privoxy</span> will not be involved. Flush
      the browser's caches, and then try again.</p>

      <p>If this doesn't help, you probably have an error in the rule you
      applied. Try pasting the full URL of the offending ad into <a href=
      "http://config.privoxy.org/show-url-info" target=
      "_top">http://config.privoxy.org/show-url-info</a> and see if it really
      matches your new rule. Blocking ads is like blocking spam: a lot of
      tinkering is required to stay ahead of the game. And remember you need
      to block the URL of the ad in question, which may be entirely different
      from the site URL itself. Most ads are hosted on different servers than
      the main site itself. If you right-click on the ad, you should be able
      to get all the relevant information you need. Alternately, you can find
      the correct URL by looking at <span class=
      "APPLICATION">Privoxy's</span> logs (you may need to enable logging in
      the main config file if its disabled).</p>

      <p>Below is a slightly modified real-life log snippet that originates
      with one requested URL: <tt class="LITERAL">www.example.com</tt> (name
      of site was changed for this example, the number of requests is real).
      You can see in this the complexity of what goes into making up this one
      <span class="QUOTE">"page"</span>. There are eight different domains
      involved here, with thirty two separate URLs requested in all, making
      up all manner of images, Shockwave Flash, JavaScript, CSS stylesheets,
      scripts, and other related content. Some of this content is obviously
      <span class="QUOTE">"good"</span> or <span class="QUOTE">"bad"</span>,
      but not all. Many of the more questionable looking requests, are going
      to outside domains that seem to be identifying themselves with
      suspicious looking names, making our job a little easier. <span class=
      "APPLICATION">Privoxy</span> has <span class="QUOTE">"crunched"</span>
      (meaning caught and BLOCKED) quite a few items in this example, but
      perhaps missed a few as well.</p>

      <table class="c2" border="0" width="100%">
        <tr>
          <td>
            <pre class="SCREEN">
Request: www.example.com/
Request: www.example.com/favicon.ico
Request: img.example.com/main.css
Request: img.example.com/sr.js
Request: example.betamarker.com/example.html
Request: www.lik-sang.com/Banners/bestsellers/skyscraper.php?likref=BSellers
Request: img.example.com/pb.png
Request: www.google-analytics.com/urchin.js crunch! (Blocked)
Request: www.advertising-department.com/ats/switch.ps.php?26856 crunch! (Blocked)
Request: img.example.com/p.gif
Request: www.popuptraffic.com/assign.php?l=example&amp;mode=behind crunch! (Blocked)
Request: www.popuptraffic.com/scripts/popup.php?hid=5c3cf&amp;tmpl=PBa.tmpl crunch! (Blocked)
Request: www.popuptraffic.com/assign.php?l=example crunch! (Blocked)
Request: www.lik-sang.com/Banners/best_sellers/best_sellers.css
Request: www.adtrak.net/adx.js crunch! (Blocked)
Request: img.example.com/hbg.gif
Request: img.example.com/example.jpg
Request: img.example.com/mt.png
Request: img.example.com/mm.png
Request: img.example.com/mb.png
Request: www.popuptraffic.com/scripts/popup.php?hid=a71b91fa5&amp;tmpl=Ua.tmp crunch! (Blocked)
Request: www.example.com/tracker.js
Request: www.lik-sang.com/Banners/best_sellers/lsi_head.gif
Request: www.adtrak.net/adjs.php?n=020548130&amp;what=zone:61 crunch! (Blocked)
Request: www.adtrak.net/adjs.php?n=463594413&amp;what=zone:58&amp;source=Ua crunch! (Blocked)
Request: www.lik-sang.com/Banners/best_sellers/bottomani.swf
Request: mmm.elitemediagroup.net/install.php?allowpop=no&amp;popupmincook=0&amp;allowsp2=1 crunch! (Blocked)
Request: www.example.com/tracker.js?screen=1400x1050&amp;win=962x693
Request: www.adtrak.net/adlog.php?bannerid=1309&amp;clientid=439&amp;zoneid=61 crunch! (Blocked)
Request: 66.70.21.80/scripts/click.php?hid=5c3cf599a9efd0320d26&amp;si
Request: 66.70.21.80/img/pixel.gif
Request: www.adtrak.net/adlog.php?bannerid=1309&amp;clientid=439&amp;zoneid=58&amp;source=Ua&amp;block=86400 crunch! (Blocked)
Request: 66.70.21.80/scripts/click.php?hid=a71b9f6504b0c5681fa5&amp;si=Ua
</pre>
          </td>
        </tr>
      </table>

      <p>Despite 12 out of 32 requests being blocked, the page looked, and
      seemed to behave perfectly <span class="QUOTE">"normal"</span> (minus
      some ads, of course).</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="BADSITE" id="BADSITE">5.4. One of my
      favorite sites does not work with Privoxy. What can I do?</a></h3>

      <p>First verify that it is indeed a <span class=
      "APPLICATION">Privoxy</span> problem, by toggling off <span class=
      "APPLICATION">Privoxy</span> through <a href=
      "http://config.privoxy.org/toggle" target=
      "_top">http://config.privoxy.org/toggle</a> (the toggle feature may
      need to be enabled in the main <tt class="FILENAME">config</tt>), and
      then shift-reloading the problem page (i.e. holding down the shift key
      while clicking reload. Alternatively, flush your browser's disk and
      memory caches).</p>

      <p>If the problem went away, we know we have a configuration related
      problem. Now go to <a href="http://config.privoxy.org/show-url-info"
      target="_top">http://config.privoxy.org/show-url-info</a> and paste the
      full URL of the page in question into the prompt. See which actions are
      being applied to the URL, and which matches in which actions files are
      responsible for that. It might be helpful also to look at your logs for
      this site too, to see what else might be happening (note: logging may
      need to be enabled in the main config file). Many sites are complex and
      require a number of related pages to help present their content. Look
      at what else might be used by the page in question, and what of that
      might be <span class="emphasis EMPHASIS c3">required</span>. Now, armed
      with this information, go to <a href=
      "http://config.privoxy.org/show-status" target=
      "_top">http://config.privoxy.org/show-status</a> and select the
      appropriate actions files for editing.</p>

      <p>You can now either look for a section which disables the actions
      that you suspect to cause the problem and add a pattern for your site
      there, or make up a completely new section for your site. In any case,
      the recommended way is to disable only the prime suspect, reload the
      problem page, and only if the problem persists, disable more and more
      actions until you have identified the culprit. You may or may not want
      to turn the other actions on again. Remember to flush your browser's
      caches in between any such changes!</p>

      <p>Alternately, if you are comfortable with a text editor, you can
      accomplish the same thing by editing the appropriate actions file.
      Probably the easiest way to deal with such problems when editing by
      hand is to add your site to a <tt class="LITERAL">{ fragile }</tt>
      section in <tt class="FILENAME">user.action</tt>, which is an alias
      that turns off most <span class="QUOTE">"dangerous"</span> actions, but
      is also likely to turn off more actions then needed, and thus lower
      your privacy and protection more than necessary,</p>

      <p>Troubleshooting actions is discussed in more detail in the <a href=
      "../user-manual/appendix.html#ACTIONSANAT" target="_top">User Manual
      appendix, Troubleshooting: the Anatomy of an Action</a>. There is also
      an <a href="../user-manual/actions-file.html#ACT-EXAMPLES" target=
      "_top">actions tutorial</a> with general configuration information and
      examples.</p>

      <p>As a last resort, you can always see if your browser has a setting
      that will bypass the proxy setting for selective sites. Modern browsers
      can do this.</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="DUN" id="DUN">5.5. After installing Privoxy,
      I have to log in every time I start IE. What gives?</a></h3>

      <p>This is a quirk that effects the installation of <span class=
      "APPLICATION">Privoxy</span>, in conjunction with Internet Explorer and
      Internet Connection Sharing on Windows 2000 and Windows XP. The
      symptoms may appear to be corrupted or invalid DUN settings, or
      passwords.</p>

      <p>When setting up an NT based Windows system with <span class=
      "APPLICATION">Privoxy</span> you may find that things do not seem to be
      doing what you expect. When you set your system up you will probably
      have set up Internet Connection Sharing (ICS) with Dial up Networking
      (DUN) when logged in with administrator privileges. You will probably
      have made this DUN connection available to other accounts that you may
      have set-up on your system. E.g. Mum or Dad sets up the system and
      makes accounts suitably configured for the kids.</p>

      <p>When setting up <span class="APPLICATION">Privoxy</span> in this
      environment you will have to alter the proxy set-up of Internet
      Explorer (IE) for the specific DUN connection on which you wish to use
      <span class="APPLICATION">Privoxy</span>. When you do this the ICS DUN
      set-up becomes user specific. In this instance you will see no
      difference if you change the DUN connection under the account used to
      set-up the connection. However when you do this from another user you
      will notice that the DUN connection changes to make available to "Me
      only". You will also find that you have to store the password under
      each different user!</p>

      <p>The reason for this is that each user's set-up for IE is user
      specific. Each set-up DUN connection and each LAN connection in IE
      store the settings for each user individually. As such this enforces
      individual configurations rather than common ones. Hence the first time
      you use a DUN connection after re-booting your system it may not
      perform as you expect, and prompt you for the password. Just set and
      save the password again and all should be OK.</p>

      <p>[Thanks to Ray Griffith for this submission.]</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="FTP" id="FTP">5.6. I cannot connect to any
      FTP sites. Privoxy is blocking me.</a></h3>

      <p><span class="APPLICATION">Privoxy</span> cannot act as a proxy for
      FTP traffic, so do not configure your browser to use <span class=
      "APPLICATION">Privoxy</span> as an FTP proxy. The same is true for
      <span class="emphasis EMPHASIS c3">any protocol other than HTTP or
      HTTPS (SSL)</span>.</p>

      <p>Most browsers understand FTP as well as HTTP. If you connect to a
      site, with a URL like <tt class="LITERAL">ftp://ftp.example.com</tt>,
      your browser is making an FTP connection, and not a HTTP connection. So
      while your browser may speak FTP, <span class=
      "APPLICATION">Privoxy</span> does not, and cannot proxy such
      traffic.</p>

      <p>To complicate matters, some systems may have a generic <span class=
      "QUOTE">"proxy"</span> setting, which will enable various protocols,
      including <span class="emphasis EMPHASIS c3">both</span> HTTP and FTP
      proxying! So it is possible to accidentally enable FTP proxying in
      these cases. And of course, if this happens, <span class=
      "APPLICATION">Privoxy</span> will indeed cause problems since it does
      not know FTP. Newer version will give a sane error message if a FTP
      connection is attempted. Just disable the FTP setting and all will be
      well again.</p>

      <p>Will <span class="APPLICATION">Privoxy</span> ever proxy FTP
      traffic? Unlikely. There just is not much reason, and the work to make
      this happen is more than it may seem.</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="MACOSXIE" id="MACOSXIE">5.7. In Mac OS X, I
      can't configure Microsoft Internet Explorer to use Privoxy as the HTTP
      proxy.</a></h3>

      <p>Microsoft Internet Explorer (in versions like 5.1) respects
      system-wide network settings. In order to change the HTTP proxy, open
      System Preferences, and click on the Network icon. In the settings pane
      that comes up, click on the Proxies tab. Ensure the "Web Proxy (HTTP)"
      checkbox is checked and enter <tt class="LITERAL">127.0.0.1</tt> in the
      entry field. Enter <tt class="LITERAL">8118</tt> in the Port field. The
      next time you start IE, it should reflect these values.</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="MACOSXUNINSTALL" id="MACOSXUNINSTALL">5.8.
      In Mac OS X, I dragged the Privoxy folder to the trash in order to
      uninstall it. Now the finder tells me I don't have sufficient
      privileges to empty the trash.</a></h3>

      <p>Note: This ONLY applies to privoxy 3.0.6 and earlier.</p>

      <p>Just dragging the <span class="APPLICATION">Privoxy</span> folder to
      the trash is not enough to delete it. <span class=
      "APPLICATION">Privoxy</span> supplies an <span class=
      "APPLICATION">uninstall.command</span> file that takes care of these
      details. Open the trash, drag the <span class=
      "APPLICATION">uninstall.command</span> file out of the trash and
      double-click on it. You will be prompted for confirmation and the
      administration password.</p>

      <p>The trash may still appear full after this command; emptying the
      trash from the desktop should make it appear empty again.</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="MACOSXIMAGES" id="MACOSXIMAGES">5.9. In Mac
      OS X Panther (10.3), images often fail to load and/or I experience
      random delays in page loading. I'm using <tt class=
      "LITERAL">localhost</tt> as my browser's proxy setting.</a></h3>

      <p>We believe this is due to an IPv6-related bug in Mac OS X, but don't
      fully understand the issue yet. In any case, changing the proxy setting
      to <tt class="LITERAL">127.0.0.1</tt> instead of <tt class=
      "LITERAL">localhost</tt> works around the problem.</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="BLANKPAGE" id="BLANKPAGE">5.10. I get a
      completely blank page at one site. <span class="QUOTE">"View
      Source"</span> shows only: <span class=
      "MARKUP">&lt;html&gt;&lt;body&gt;&lt;/body&gt;&lt;/html&gt;</span>.
      Without Privoxy the page loads fine.</a></h3>

      <p>Chances are that the site suffers from a bug in <a href=
      "http://www.php.net/" target="_top"><span class=
      "APPLICATION">PHP</span></a>, which results in empty pages being sent
      if the client explicitly requests an uncompressed page, like
      <span class="APPLICATION">Privoxy</span> does. This bug has been fixed
      in PHP 4.2.3.</p>

      <p>To find out if this is in fact the source of the problem, try adding
      the site to a <tt class="LITERAL">-prevent-compression</tt> section in
      <tt class="FILENAME">user.action</tt>:</p>

      <table class="c2" border="0" width="100%">
        <tr>
          <td>
            <pre class="SCREEN">
   # Make exceptions for ill-behaved sites:
   #
   {-prevent-compression}
    .example.com
</pre>
          </td>
        </tr>
      </table>

      <p>If that works, you may also want to report the problem to the site's
      webmasters, telling them to use zlib.output_compression instead of
      ob_gzhandler in their PHP applications (workaround) or upgrade to PHP
      4.2.3 or later (fix).</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="NOHOSTNAME" id="NOHOSTNAME">5.11. My logs
      show many <span class="QUOTE">"Unable to get my own hostname"</span>
      lines. Why?</a></h3>

      <p><span class="APPLICATION">Privoxy</span> tries to get the hostname
      of the system its running on from the IP address of the system
      interface it is bound to (from the <tt class="FILENAME">config</tt>
      file <span class="emphasis EMPHASIS c3">listen-address</span> setting).
      If the system cannot supply this information, <span class=
      "APPLICATION">Privoxy</span> logs this condition.</p>

      <p>Typically, this would be considered a minor system configuration
      error. It is not a fatal error to <span class=
      "APPLICATION">Privoxy</span> however, but may result in a much slower
      response from <span class="APPLICATION">Privoxy</span> on some
      platforms due to DNS timeouts.</p>

      <p>This can be caused by a problem with the local <tt class=
      "FILENAME">hosts</tt> file. If this file has been changed from the
      original, try reverting it to see if that helps. Make sure whatever
      name(s) are used for the local system, that they resolve both ways.</p>

      <p>You should also be able to work around the problem with the <a href=
      "../user-manual/config.html#HOSTNAME" target="_top">hostname
      option</a>.</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="INUSE" id="INUSE">5.12. When I try to launch
      Privoxy, I get an error message <span class="QUOTE">"port 8118 is
      already in use"</span> (or similar wording). Why?</a></h3>

      <p>Port 8118 is <span class="APPLICATION">Privoxy's</span> default TCP
      <span class="QUOTE">"listening"</span> port. Typically this message
      would mean that there is already one instance of <span class=
      "APPLICATION">Privoxy</span> running, and your system is actually
      trying to start a second <span class="APPLICATION">Privoxy</span> on
      the same port, which will not work. (You can have multiple instances
      but they must be assigned different ports.) How and why this might
      happen varies from platform to platform, but you need to check your
      installation and start-up procedures.</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="DEMORONIZER" id="DEMORONIZER">5.13. Pages
      with UTF-8 fonts are garbled.</a></h3>

      <p>This is caused by the <span class="QUOTE">"demoronizer"</span>
      filter. You should either upgrade <span class=
      "APPLICATION">Privoxy</span>, or at least upgrade to the most recent
      <tt class="FILENAME">default.action</tt> file available from <a href=
      "http://sourceforge.net/project/showfiles.php?group_id=11118" target=
      "_top">SourceForge</a>. Or you can simply disable the demoronizer
      filter.</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="DEMORONIZER2" id="DEMORONIZER2">5.14. Why
      are binary files (such as images) corrupted when Privoxy is
      used?</a></h3>

      <p>This may also be caused by the <span class=
      "QUOTE">"demoronizer"</span> filter, in conjunction with a web server
      that is misreporting the content type. Binary files are exempted from
      <span class="APPLICATION">Privoxy's</span> filtering (unless the web
      server by mistake says the file is something else). Either upgrade
      <span class="APPLICATION">Privoxy</span>, or go to the most recent
      <tt class="FILENAME">default.action</tt> file available from <a href=
      "http://sourceforge.net/project/showfiles.php?group_id=11118" target=
      "_top">SourceForge</a>.</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="DEMORONIZER3" id="DEMORONIZER3">5.15. What
      is the <span class="QUOTE">"demoronizer"</span> and why is it
      there?</a></h3>

      <p>The original demoronizer was a Perl script that cleaned up HTML
      pages which were created with certain Microsoft products. MS has used
      proprietary extensions to standardized font encodings (ISO 8859-1),
      which has caused problems for pages that are viewed with non-Microsoft
      products (and are expecting to see a standard set of fonts). The
      demoronizer corrected these errors so the pages displayed correctly.
      <span class="APPLICATION">Privoxy</span> borrowed from this script,
      introducing a filter based on the original demoronizer, which in turn
      could correct these errors on the fly.</p>

      <p>But this is only needed in some situations, and will cause serious
      problems in some other situations.</p>

      <p>If you are using Microsoft products, you do not need it. If you need
      to view pages with UTF-8 characters (such as Cyrillic or Chinese), then
      it will cause corruption of the fonts, and thus <span class=
      "emphasis EMPHASIS c3">should not be on</span>.</p>

      <p>On the other hand, if you use non-Microsoft products, and you
      occasionally notice weird characters on pages, you might want to try
      it.</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="WINDOWOPEN" id="WINDOWOPEN">5.16. Why do I
      keep seeing <span class="QUOTE">"PrivoxyWindowOpen()"</span> in raw
      source code?</a></h3>

      <p><span class="APPLICATION">Privoxy</span> is attempting to disable
      malicious <a href="http://en.wikipedia.org/wiki/Javascript" target=
      "_top">Javascript</a> in this case, with the <tt class=
      "LITERAL">unsolicited-popups</tt> filter. <span class=
      "APPLICATION">Privoxy</span> cannot tell very well <span class=
      "QUOTE">"good"</span> code snippets from <span class=
      "QUOTE">"bad"</span> code snippets.</p>

      <p>If you see this in HTML source, and the page displays without
      problems, then this is good, and likely some pop-up window was
      disabled. If you see this where it is causing a problem, such as a
      downloaded program source code file, then you should set an exception
      for this site or page such that the integrity of the page stays in tact
      by disabling all filtering.</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="DNSERRORS" id="DNSERRORS">5.17. I am getting
      too many DNS errors like <span class="QUOTE">"404 No Such
      Domain"</span>. Why can't Privoxy do this better?</a></h3>

      <p>There are potentially several factors here. First of all, the DNS
      resolution is done by the underlying operating system -- not
      <span class="APPLICATION">Privoxy</span> itself. <span class=
      "APPLICATION">Privoxy</span> merely initiates the process and hands it
      off, and then later reports whatever the outcome was and tries to give
      a coherent message if there seems to be a problem. In some cases, this
      might otherwise be mitigated by the browser itself which might try some
      work-arounds and alternate approaches (e.g adding <span class=
      "QUOTE">"www."</span> to the URL).</p>

      <p>In other cases, if <span class="APPLICATION">Privoxy</span> is being
      chained with another proxy, this could complicate the issue, and cause
      undue delays and timeouts. In the case of a <span class=
      "QUOTE">"socks4a"</span> proxy, the socks server handles all the DNS.
      <span class="APPLICATION">Privoxy</span> would just be the <span class=
      "QUOTE">"messenger"</span> which is reporting whatever problem occurred
      downstream, and not the root cause of the error.</p>

      <p>In any case, versions newer than 3.0.3 include various improvements
      to help <span class="APPLICATION">Privoxy</span> better handle these
      cases.</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="ALLCPU" id="ALLCPU">5.18. At one site
      Privoxy just hangs, and starts taking all CPU. Why is this?</a></h3>

      <p>This is probably a manifestation of the <span class="QUOTE">"100%
      cpu"</span> problem that occurs on pages containing many (thousands
      upon thousands) of blank lines. The blank lines are in the raw HTML
      source of the page, and the browser just ignores them. But the pattern
      matching in <span class="APPLICATION">Privoxy's</span> page filtering
      mechanism is trying to match against absurdly long strings and this
      becomes very CPU-intensive, taking a long, long time to complete.</p>

      <p>Until a better solution comes along, disable filtering on these
      pages, particularly the <tt class="LITERAL">js-annoyances</tt> and
      <tt class="LITERAL">unsolicited-popups</tt> filters. If you run into
      this problem with a recent <span class="APPLICATION">Privoxy</span>
      version, please send a problem report.</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="SLOWCRAWL" id="SLOWCRAWL">5.19. I just
      installed Privoxy, and all my browsing has slowed to a crawl. What
      gives?</a></h3>

      <p>This should not happen, and for the overwhelming number of users
      world-wide, it does not happen. I would suspect some inadvertent
      interaction of software components such as anti-virus software, spyware
      protectors, personal firewalls or similar components. Try disabling (or
      uninstalling) these one at a time and see if that helps. Either way, if
      you are using a recent <span class="APPLICATION">Privoxy</span>
      version, please report the problem.</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="PREVENTCOMP" id="PREVENTCOMP">5.20. Why do
      my filters work on some sites but not on others?</a></h3>

      <p>It's probably due to compression. It is a common practice for web
      servers to send their content <span class="QUOTE">"compressed"</span>
      in order to speed things up, and then let the browser <span class=
      "QUOTE">"uncompress"</span> them. When compiled with zlib support
      <span class="APPLICATION">Privoxy</span> can decompress content before
      filtering, otherwise you may want to enable <a href=
      "../user-manual/actions-file.html#PREVENT-COMPRESSION" target=
      "_top">prevent-compression</a>.</p>

      <p>As of <span class="APPLICATION">Privoxy</span> 3.0.9, zlib support
      is enabled in the default builds.</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="SSL-WARNINGS" id="SSL-WARNINGS">5.21. On
      some HTTPS sites my browser warns me about unauthenticated content, the
      URL bar doesn't get highlighted and the lock symbol appears to be
      broken. What's going on?</a></h3>

      <p>Probably the browser is requesting ads through HTTPS and
      <span class="APPLICATION">Privoxy</span> is blocking the requests.
      Privoxy's error messages are delivered unencrypted and while it's
      obvious for the browser that the HTTPS request is already blocked by
      the proxy, some warn about unauthenticated content anyway.</p>

      <p>To work around the problem you can redirect those requests to an
      invalid local address instead of blocking them. While the redirects
      aren't encrypted either, many browsers don't care. They simply follow
      the redirect, fail to reach a server and display an error message
      instead of the ad.</p>

      <p>To do that, enable logging to figure out which requests get blocked
      by <span class="APPLICATION">Privoxy</span> and add the hosts (no path
      patterns) to a section like this:</p>

      <table class="c2" border="0" width="100%">
        <tr>
          <td>
            <pre class="SCREEN">
{+redirect{http://127.0.0.1:0/} -block -limit-connect}
.ivwbox.de:443/
</pre>
          </td>
        </tr>
      </table>

      <p>Additionally you have to configure your browser to contact
      <span class="QUOTE">"127.0.0.1:0"</span> directly (instead of through
      <span class="APPLICATION">Privoxy</span>).</p>

      <p>To add a proxy exception in <span class="APPLICATION">Mozilla
      Firefox</span> open the <span class="QUOTE">"Preferences"</span>, click
      the <span class="QUOTE">"Settings"</span> button located on the
      <span class="QUOTE">"Network"</span> tab in the <span class=
      "QUOTE">"Advanced"</span> section, and add <span class=
      "QUOTE">"127.0.0.1:0"</span> in the <span class="QUOTE">"No Proxy
      for:"</span> field.</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="SE-LINUX" id="SE-LINUX">5.22. I get selinux
      error messages. How can I fix this?</a></h3>

      <p>Please report the problem to the creator of your selinux
      policies.</p>

      <p>The problem is that some selinux policy writers aren't familiar with
      the application they are trying to <span class="QUOTE">"secure"</span>
      and thus create policies that make no sense.</p>

      <p>In <span class="APPLICATION">Privoxy's</span> case the problem
      usually is that the policy only allows outgoing connections for certain
      destination ports (e.g. 80 and 443). While this may cover the standard
      ports, websites occasionally use other ports as well. This isn't a
      security problem and therefore <span class=
      "APPLICATION">Privoxy's</span> default configuration doesn't block
      these requests.</p>

      <p>If you really want to block these ports (and don't be able to load
      websites that don't use standard ports), you should configure Privoxy
      to block these ports as well, so it doesn't trigger the selinux
      warnings.</p>
    </div>

    <div class="SECT2">
      <h3 class="SECT2"><a name="GENTOO-RICERS" id="GENTOO-RICERS">5.23. I
      compiled <span class="APPLICATION">Privoxy</span> with Gentoo's portage
      and it appears to be very slow. Why?</a></h3>

      <p>Probably you unintentionally compiled <span class=
      "APPLICATION">Privoxy</span> without threading support in which case
      requests have to be serialized and only one can be served at the same
      time.</p>

      <p>Check your <span class="QUOTE">"USE"</span> flags and make sure they
      include <span class="QUOTE">"threads"</span>. If they don't, add the
      flag and rebuild <span class="APPLICATION">Privoxy</span>.</p>

      <p>If you compiled <span class="APPLICATION">Privoxy</span> with
      threading support (on POSIX-based systems), the <span class=
      "QUOTE">"Conditional #defines"</span> section on <a href=
      "http://config.privoxy.org/show-status" target=
      "_top">http://config.privoxy.org/show-status</a> will list <span class=
      "QUOTE">"FEATURE_PTHREAD"</span> as <span class=
      "QUOTE">"enabled"</span>.</p>
    </div>
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